SOLUTION: Solve (2x+5)(6x-1)=120

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Question 559361: Solve (2x+5)(6x-1)=120
Answer by mananth(16946) About Me  (Show Source):
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(2x+5)(6x-1)=120
2x(6x-1)+5(6x-1)=120
12x^2-2x+30x-5=120
12x^2+28x-5-120=0
12x^2+28x-125=0
Find the roots of the equation by quadratic formula

a= 12 , b= 28 , c= -25

b^2-4ac= 784 + 1200
b^2-4ac= 1984
%09sqrt%28%091984%09%29=%0944.54%09
x=%28-b%2B-sqrt%28b%5E2-4ac%29%29%2F%282a%29
x1=%28-b%2Bsqrt%28b%5E2-4ac%29%29%2F%282a%29
x1=( -28 + 44.54 )/ 24
x1= 0.69
x2=( -28 -44.54 ) / 24
x2= -3.02